1. Field of the Invention
The present invention relates to a light-emitting semiconductor device (LED) or an optical semiconductor device including a light detection device and so on which has at least one p-n junction structure. Especially, the invention relates to an optical semiconductor device which has a highly resistive region to control the flow of current.
2. Description of the Related Art
Conventionally, an electrode of an optical semiconductor device, especially a nitrogen compound LED having at least one of gallium (Ga), aluminum (Al), and indium (In) therein, is formed at a corner of the semiconductor chip so as not to effectively interfere with light produced by the device. The electrode is formed using bonding processes.
However, an opaque electrode pad is formed on some part or area of the electrode so that emission light from an area below the electrode pad is unable to contribute to luminous intensity of the device. The electric current which contributes to such blocked light is thus not used effectively.
Such unnecessary current flow causes the LED to age, because the region below the electrode pad is expected to be mechanically damaged at the time of wire bonding and the unnecessary current flow through that region increases the deterioration of the LED. As a result, the life span of the LED is limited, making the LED an unreliable product.